Peter Davey

Biochar was evaluated for its effectiveness as a manure lagoon cover. It could have a future use as a nutrient-rich soil amendment. Photo credit Brian Dougherty.

Biochar was evaluated for its effectiveness as a manure lagoon cover. It could have a future use as a nutrient-rich soil amendment. Photo credit Brian Dougherty.

Manure can be a useful fertilizer, returning valued nitrogen, phosphorus and potassium to the soil for plant growth. But manure has problems. Odour offensiveness, gas emissions, nutrient runoff, and possible water pollution are just a few.

Timing is also a problem. Livestock produce manure 24/7 – even when it is impractical or unwise to move it to the field. Delivering manure to the field needs to be timed to nutrient needs, soil moisture levels, and temperature. Manure storage lagoons can hold the manure until the time is ripe, but don’t solve odour and harmful gas emissions.

Biochar is plant matter, such as straw, woody debris, or corn stalks, that has been heated to high temperatures in a low- to no-oxygen environment. The result is a black, carbon-rich material similar to charcoal.

“Biochar provides a structure with lots of empty pore space,” said Dougherty. “The outer surface may appear small but the interior surface area is absolutely massive. A few ounces of biochar can have an internal surface area the size of a football field. There is a lot of potential there for holding on to water and nutrients.”

In addition to its hidden storage capacity, the surface of the biochar tends to have a chemical charge. This gives biochar the ability to attract and hold nitrogen, phosphorus, and potassium ions, metals, and other compounds. Biochar can also float (some types more than others), allowing it to trap gases at the water’s surface.

Dougherty’s research studied two liquid dairy manures with differing nutrient levels. It also studied two types of biochars, made at different temperatures. Biochar is somewhat fickle, showcasing different properties when created at different temperatures. Dougherty also included pails of manure with a straw cover for comparison, and pails with no cover as a control.

The research found that the biochars picked up the most nutrients from the more concentrated manure with a higher nutrient content. Nitrogen, phosphorus and potassium are nutrients with the greatest economic value on a farm, but applying them in excess of what the crop can take up can lead to nutrient loss to the watershed.

Ammonia was also measured at the top of each pail as ammonia and sulfates are the main sources of manure odour. The cooler-crafted biochar performed best, reducing ammonia by 72% – 80%. It also floated better. However, since it floated better and tended to repel water, it was less effective at attracting and holding nutrients than the warmer-crafted biochar.

As part of the experiment, gas release from manure covered in different materials was measured in a temperature-regulated greenhouse. Photo credit Brian Dougherty.

To test how biochar improved lagoon odour, Dougherty recruited a panel of judges. However, freezing temperatures and rain affected the odour intensity over the 12 week trial. Despite this, three different biochars were shown to reduce odour from liquid dairy manure, whereas a straw cover was not effective.

“Determining the best trade-off of biochar properties will be an important next step,” Dougherty says. “More research could find the right biochar production temperature, particle size, pH, and float properties. The potential is there.”

While biochar is currently more expensive than straw, it could offer other economic benefits. Excess farm and forestry material could be used to create biochar on-site, while generating energy that could be used for heat during colder months. There is also potential for generating electricity, fuels, and other by-products using more sophisticated equipment. Also, after its use in the lagoon, the biochar could be spread on fields as needed. Any excess could be sold as a high-value fertilizer product.

In addition, biochar has environmental benefits. “Anything you can do to prevent gases from escaping the lagoon is a good thing,” Dougherty said. “Biochar applied to soils — particularly poorer quality soils — is very helpful. Making biochar can also help reduce atmospheric carbon dioxide levels. A portion of the carbon dioxide that was taken in during plant growth ends up as a very stable form of carbon in the soil. The overall picture has multiple benefits.”

Dougherty’s biochar research is published inJournal of Environmental Quality. Oregon State University’s Agriculture Research Foundation and Agricultural Sciences Bioenergy Education Program funded this research.

British Columbia’s Minister of Environment and Climate Change Strategy George Heyman announced on August 2, 2017, a new review of the Hullcar Aquifer, with the end goal of ensuring agricultural practices are consistent with the provision and protection of clean, safe drinking water.

Due to high levels of nitrates, the Interior Health Authority issued a water quality advisory for residents in Hullcar Aquifers 102 and 103 on July 14, 2014.

The Ministry of the Environment said the most common sources of nitrate substances are human activities, including agricultural activities, wastewater treatment, and discharges from industrial processes and motor vehicles. Most nitrate reduction in the soil occurs through plant uptake and utilization, whereas surplus nitrates readily leach into groundwater.

In the announcement, the Minister said an independent, respected expert is being commissioned to lead the review, which will be due to government by the end of September 2017. The review will look at decisions and actions taken to-date with respect to pollution in the Hullcar Aquifer. It is expected to provide forward-looking recommendations to help inform best practices for the agricultural sector and improvements to regulations that can be applied province-wide.

The IWSFG is comprised of water associations, utilities and professionals seeking to provide clear guidance on what should and should not be flushed down the toilet, to protect customers, wastewater systems, their workers, and the environment.

The IWSFG has developed criteria for items that can be flushed down the toilet. These criteria seek to address the key aspects of the International Water Industry Statement on Flushability that was released on September 22, 2016, and signed by over 250 water organizations worldwide, that to be flushable a product must:

Break into small pieces quickly;

Not be buoyant;

Not contain plastic or regenerated cellulose but only contain materials which will readily degrade in a range of natural environments.

On July 24, 2017, the IWSFG released its draft flushability standards for public comment. Comments are due September 1, 2017. The IWSFG will then meet to address the comments and where agreed by the group, amend the standard. The process to approve the final standards will be consistent with that used by the International Organisation for Standardization (ISO).

Researchers from the Cambridge Centre for Smart Infrastructure and Construction attach sensors to a test pipe in Cornell’s Geotechnical Lifelines Large-Scale Testing Facility.

Researchers from the Cambridge Centre for Smart Infrastructure and Construction attach sensors to a test pipe in Cornell’s Geotechnical Lifelines Large-Scale Testing Facility.

By Syl Kacapyr

The future looks “smart” for underground infrastructure after a first-of-its-kind experiment was recently conducted at the Cornell University’s Geotechnical Lifelines Large-Scale Testing Facility.

Like many of today’s household devices, modern infrastructure is gaining the ability to collect and exchange valuable data, using wireless devices that monitor the health of buildings and bridges, for example, in real time. But, wireless systems for underground infrastructure, such as utility pipelines, are much more difficult to test in the field, especially during rare and extreme events such as earthquakes.

The Cornell facility tested several advanced sensors developed by researchers at the University of California, Berkeley, and the University of Cambridge Centre for Smart Infrastructure and Construction. The sensors, which can collectively measure strain, temperature, movement and leakage, were installed along a 13-metre section of a hazard-resilient pipeline being tested for earthquake fault-rupture performance.

The pipeline is produced by IPEX, using a molecularly-oriented polyvinylchloride material engineered to stretch, bend and compress as it withstands extreme ground deformation, similar to that occurring during earthquakes, floods and construction-related activity. Engineers from Oakland, California, and Vancouver, British Columbia, traveled to Cornell to watch as the pipe experienced a simulated fault rupture, while buried inside a hydraulically powered “split basin” filled with 72 tonnes of soil.

The test was the first use of the advanced sensors for the purpose of monitoring buried infrastructure, and gave an unprecedented look at the pipe’s ability to elongate and bend while being subject to ground failure.

“It was able to accommodate 50% more ground deformation than the last design, based on modifications Cornell suggested from our testing four years ago,” said Brad Wham, a geotechnical engineering postdoctoral associate at Cornell.

In addition to the scores of instruments installed for the large-scale test, new technologies employed included:

Distributed strain sensing – A laser pulse is injected through an optical fibre cable glued to a pipe. By examining the interaction signal that is generated at every point of the fibre, it is possible to obtain strain values continuously along the pipeline.

Fibre Bragg grating sensing – A special fibre optic line that splits and diffracts light into wavelengths, allowing it to monitor bending and axial deformations accurately at discrete points, especially at pipe joints.

Frequency-domain reflectometry, wireless sensor network – Metal prongs that use an electric field to measure changes in soil moisture and detect leaks. The device is battery powered and can wirelessly transmit data through soil, using a coupled magnetic induction and electromagnetic wireless sensor network system.

Smart joint-opening detection – Small magnets are attached at pipe joint locations. Once a pipe has stretched or compressed to a specific limit, the magnets conjoin to trigger the wireless sensor network to initiate the monitoring.

The sensors drew interest from the attending municipal engineers, who need new ways to monitor the performance of underground infrastructure. As cities begin to adopt sensor technologies, more data will exist, not just for infrastructure, but for the surrounding environment as well.

“You can learn something about sources of subsidence or corrosion that affect other structures, or something about the geographic distribution of earthquake or hurricane damage, which then allows you to make improved decisions about emergency response,” said Tom O’Rourke, professor of civil and environmental engineering and principal investigator of the research project.

The test also proved that sensors provide valuable feedback to companies like IPEX that want to advance the engineering behind new products and improve system-wide performance.

“This is about having feedback and intelligence for underground lifeline systems, such as water supplies, electric power and telecommunications, which provide the services and resources that define a modern city,” O’Rourke said. “It’s pretty clear to me that within 20 years there will be intelligence integrated into every aspect of infrastructure.”

“The vision we have is that future infrastructure looks after itself by sensing and adapting to the changing environment,” said Kenichi Soga, professor at Berkeley and principal investigator for the Berkeley and Cambridge teams. “Rapidly developing sensor technologies and data analytics give us the opportunity to make this happen.”

The research team will excavate the pipeline and analyze the massive amount of data collected by the sensors. “It’s going to be game-changing,” said Wham, who added that some of the devices are capable of recording up to a thousand measurements per second or more. “We have many, many gigs of data right now for measurements that were previously unattainable.”

Legionnaires’ disease, a severe and potentially deadly form of pneumonia, is increasingly a threat to public health. Canada made headlines when news surfaced of a major Legionnaires’ disease outbreak in Quebec City in 2012. The outbreak infected 181 people and caused 13 deaths. Almost two-thirds of the affected were men, and the average age of those infected was 62.

The determination that an outbreak was underway was made two weeks after the first reported case, and letters requesting all owners of buildings with three or more stories to disinfect their cooling towers went out shortly thereafter. After an extensive process of cooling tower mapping, sampling and disinfection, the source of the outbreak was finally identified, 67 days after the first case. During the investigation, Legionella pneumophila serogroup 1 isolates from area cooling towers were compared to the L. pneumophila isolate from patients until there was a conclusive match at one of the 16 buildings where L. pneumophila had been found.

In 2014, monthly cooling tower monitoring for L. pneumophila with a culture method became mandatory in Quebec.

In response to this tragic outbreak, an inter-ministerial working group was convened and new cooling tower regulations were implemented in less than 18 months. These regulations include cooling tower registration, a requirement to maintain towers according to a professionally designed plan that is tailored to the individual system, and a recommendation for regular monitoring for L. pneumophila using a culture method. In 2014, monthly cooling tower monitoring for L. pneumophila with a culture method became mandatory in Quebec.

While Quebec’s regulations are the most visible and far-reaching, Canada has been at the forefront of Legionnaires’ disease prevention in other arenas as well. In response to clusters of 10–11 cases of legionellosis in 2006 and again in 2008, the City of Hamilton, Ontario, and Hamilton Public Health Service implemented mandatory cooling tower registrations in 2011.

Throughout Canada, the Government Works and Public Services Standard MD 15161–2013: Control of Legionella in Mechanical Systems provides “minimum requirements for design, operation, maintenance, and testing to prevent legionellosis associated with building water systems in federal facilities.”

What you need to know about Legionella

Legionella bacteria can be free-living, survive in a host amoeba, or be part of biofilm. All three situations can be present in potable and non-potable water systems. People can become ill when Legionella organisms are aspirated and infect macrophages in the lungs. People at high risk for Legionnaires’ disease include those with chronic lung disease, those with compromised immune systems, and people 50 years of age or older.

In addition to the susceptibility of the patient, other key risk factors include the extent of exposure and the virulence of the strain of Legionella. Of the more than 60 species of Legionella, L. pneumophila is the species responsible for the vast majority of Legionnaires’ disease cases.

Further exacerbating the public health issue is the burgeoning threat of antibiotic resistance. According to a recent study at Tufts University, in Massachusetts, 1% – 2% of hospitalizations for infections from premise pathogens like Legionella show evidence of resistance, and those patients cost 10% – 40% more than patients with nonresistant infections.

The study’s authors warn that the lack of regulation of premise plumbing systems can lead to inconsistent monitoring and reporting of potentially dangerous deficiencies in aging infrastructure. They call for policymakers and researchers to pinpoint public health interventions that could reduce the risk of infections caused by bacteria in plumbing.

Growing demand for testing

Outbreaks of Legionnaires’ disease have been traced to North American hospitals and chain hotels just within the last year. The good news is that the spread of Legionella can be successfully managed by following thorough water safety plans, which should include periodic testing to ensure the building water system is well controlled.

The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) offers non-binding guidelines and standards establishing minimum Legionella risk management requirements for building water systems for all buildings (other than single-family residences) for potable and non-potable water. Building owners are responsible for determining whether their building water systems are at increased risk for growing and spreading Legionella and, as needed, for developing and following Legionella water safety plans that are tailored to their specific water systems. Once in place, routine testing is an essential part of measuring whether these water management plans are effectively controlling the building’s Legionella risk.

Accurate and reliable quantitative test results are required for decision makers to understand where there are the greatest risks in a water system so they can reduce them. Water-quality engineers can help building owners and the public understand the value of looking at both the concentration of Legionella at a given point in the system and frequency of Legionella-positive outlets throughout the system to gauge risk and establish appropriate control measures.

It should be noted that Legionella is virtually impossible to completely eradicate in complex water systems. However, it can be effectively controlled through proper monitoring and control measures.

Focusing detection and control efforts on L. pneumophila, the primary causative agent of Legionnaires’ disease, may increase the efficiency and efficacy of a water safety plan. L. pneumophila is the most common and clinically relevant species of Legionella. It thrives in low-nutrient conditions and grows as biofilms on the inner surfaces of pipes. Biofilms allow these pathogens to resist disinfectants and environmental stressors, and they aid in the spread of antibiotic resistance and virulence genes. Water management plans that include measures to address these conditions and effectively control L. pneumophila will also control other species of Legionella at the same time.

This focus may help building operators avoid the costs and dangers of unnecessary shutdowns and/or treatment triggered by the detection of Legionella species that are far less virulent than L. pneumophila.

State-of-the-art testing

Historically, accurate testing for Legionella has been hard to do well without years of experience. Traditional membrane filtration culture methods are complex and often require more subjectivity and expert judgment than regulators and other officials would like. Even within the canon of standard methods, variations in technique and results are common from laboratory to laboratory and even from bench to bench.

Testing protocols include many homebrew hybrids of standard culture methods that have evolved over the years as microbiologists seek to improve the precision of their counts. Indeed, some laboratories routinely run more than 11 plates to come up with a count for a single water sample.

Scientists at IDEXX have been studying the best way to detect Legionella for years. One of the difficulties in Legionella testing is to discriminate between Legionella and non-target organisms without inadvertently reducing the culturable Legionella organisms in the sample or having overgrown plates that are difficult to accurately read and count. Samples that are not readable must be retested, which often requires time-consuming resampling.

Key opinion leaders in the fields of both water quality and human disease helped identify the need for a culture test that was simple to run, met or exceeded the accuracy of existing culture methods, and could specifically detect and quantify L. pneumophila, the primary causative agent of Legionnaires’ disease.

IDEXX Legiolert® is a new culture-based method that simplifies the detection and quantification of Legionella pneumophila in potable and non-potable water samples. Legiolert has demonstrated accuracy equivalent to or greater than standard culture methods, including ISO 11731, SM9260J, and the CDC Method, per studies conducted by independent laboratories and published in peer-reviewed journals (notably, the publication of ISO 11731 comparison).

Legiolert produces a final, confirmed result for L. pneumophila in seven days and, since no confirmation steps are required, it can be up to seven days faster than traditional culture methods. Legiolert is also very simple to set up, with significantly reduced sample preparation and quality control time. After incubation, the Legiolert reagent produces an easy-to-read colorimetric signal in the presence of L. pneumophila, eliminating the need for laborious colony counting and removing subjectivity from the colony counting process.

Because of its simplicity, Legiolert is highly repeatable and reproducible. When used with the Quanti-Tray®/Legiolert method, Legiolert provides a confirmed Most Probable Number (MPN) count of up to 2,272 L. pneumophila, compared to Petri plate counting ranges, which are ≤ 200 colony forming units (CFUs). MPN quantification is a measure directly comparable to CFUs.

Beating Legionella

Investigations performed by the U.S. Centers for Disease Control and Prevention (CDC) show that almost all outbreaks of Legionnaires’ disease in the United States over the past 14 years could have been prevented with more effective water safety management programs.

Incorporating the ASHRAE standard into licensing and accreditation requirements and public health codes will substantially reduce the public health risk posed by Legionella.

Dan Broder, PhD, is a scientist with IDEXX. This article appears in ES&E Magazine’s August 2017 issue.

Work on the second stage of the Randle Reef remediation project in Hamilton, Ontario, was awarded to Milestone Environmental Contracting Inc. and Fraser River Pile & Dredge Inc., in a $32.9 million joint-venture contract announced on July 21, 2017.

The Stage Two contract is part of the three-stage $138.9 million project to clean up a heavily contaminated area of Hamilton Harbour known as Randle Reef. According to Environment and Climate Change Canada (ECCC), Randle Reef is approximately 60 hectares in size and contains 695,000 cubic metres of contaminated sediment at the bottom of the harbour. The Bay Area Restoration Council said Randle Reef is the largest polycyclic aromatic hydrocarbon contaminated sediment site in the Canadian Great Lakes.

Stage One of the project involved re-constructing an adjacent harbour pier wall and constructing an engineering containment “box” which uses double steel walls to seal in approximately 6.2 hectares of the most heavily contaminated soil.

Stage Two involves dredging contaminated sediment from the surrounding areas and placing them in the containment facility via an underwater pipeline. This stage is expected to begin in the spring of 2018 and take two years to complete.

In Stage Three, the contained sediment will be dewatered and compacted, with an impermeable cap being placed over the containment facility. This final stage is expected to be completed in 2022.

Remediation of Randle Reef is the last remaining environmental restoration project in Hamilton Harbour. According to ECCC, its completion will help remove the harbour from the list of Great Lakes Areas of Concern, and spark development along Hamilton’s waterfront and increase tourism.

Federal, provincial and municipal funding to upgrade and expand wastewater treatment facilities and stormwater management systems in the Town of Pilot Butte, Saskatchewan, was announced on July 17, 2017.

The wastewater plant upgrades include new pumping and pipeline infrastructure; an expansion and upgrade of the existing lagoon; and the addition of effluent disinfection equipment. According to Infrastructure Canada, this project will increase the Town’s capacity to support local economic growth, help to protect the environment, and allow it to expand its social and recreational services.

The total estimated cost of wastewater upgrades is $6,534,000, with the federal and provincial government each contributing up to $2,166,666 and the Town responsible for remaining costs.

Stormwater drainage infrastructure is currently under construction in the Town. When complete, this work will control erosion, prevent flooding, and reduce the burden on the sanitary sewer system. Additionally, stormwater drainage infrastructure is being improved in five other areas of the Town, which will reduce the risk of flooding damage to private and commercial properties.

The total estimated cost of stormwater improvements is estimated at $664,253. The Town will use its federal Gas Tax Fund to support this project.

The Government of Canada announced it will invest $25.7 million in the Lake Winnipeg Basin Program, with a focus on reducing nutrient pollution, enhancing collaboration to protect freshwater quality and strengthen collaboration and engagement of Indigenous people.

The announcement was made on July 24, 2017, by Minister of Environment and Climate Change, Catherine McKenna. This investment is part of the $70.5-million funding allocated for freshwater protection in the 2017 federal budget.

According to Environment and Climate Change Canada, Lake Winnipeg is the tenth largest freshwater lake in the world and the sixth largest in Canada. Its watershed covers almost a million square kilometres, encompassing four provinces and four U.S. states.

Lake Winnipeg is important to the Canadian economy, generating millions of dollars of revenue in the hydroelectricity, recreation, and commercial freshwater fishing industries. In addition, 20 Indigenous communities along the shores of Lake Winnipeg rely heavily on the lake and its surrounding lands for their livelihood, sustenance, and traditional use.

Water quality in Lake Winnipeg has deteriorated due to multiple sources of excessive nutrients (phosphorus and nitrogen) that have increased the frequency and magnitude of algal blooms, including blue-green algae. In September 2006, an algal bloom covered almost the entire surface of Lake Winnipeg.

The Lake Winnipeg Basin Initiative (LWBI) was first launched in 2008 with $18 million in funding for a five-year period. The program was renewed in 2012 for a second five-year phase, with an additional $18 million in funding. Evaluation of phase II has been finalized and the report can be read on www.canada.ca.

Environment and Climate Change Canada said it will continue to conduct science-based initiatives to reduce the effects of excess nutrients in the lake and its basin. It will also increase engagement and collaboration with Indigenous peoples, the Government of Manitoba, and all other levels of government in Canada and the United States regarding shared water resources in the basin.

Ontario’s Ministry of the Environment and Climate Change (MOECC) announced that Thomas Cavanagh Construction Limited (TCCL) was fined $220,000 on July 21, 2017, for four offences under the Ontario Water Resources Act (OWRA). TCCL had been found guilty of these offences on June 9, 2017, which were related to discharging materials into a watercourse and failing to notify the Ministry contrary to the OWRA.

According to the MOECC, TCCL was hired on January 2, 2013, to install the stormwater infrastructure at the Blackstone community, in accordance with an approved design plan. The work commenced at the end of January 2013.

The community is located on a former agricultural site located in South Kanata, Ottawa. In close proximity to the site is the Monahan Drain, which is an agricultural drainage works that flows into the Jock River and has a catchment area that supports a warm water fish habitat. The headwaters of the Drain are located at the Blackstone community.

The MOECC says that on June 11, 2013, a Rideau Valley Conservation Authority (RVCA) inspector conducted an inspection of the construction activities at the Blackstone community and observed excessive sediment discharge to the Drain. It was also noted that sediment and erosion control measures were ineffective, that the measures had not been properly maintained and were inconsistent with the approved plan. On that date, the RVCA inspector revoked the RVCA permit, and referred the matter to the Ministry.

According to the MOECC, on June 13, 2013, Ministry staff and the RVCA inspector conducted a second inspection of the site and noted that, although there had been some improvements made from two days prior, some of the control measures were still ineffective and not in line with the approved sediment and erosion control measures plan.

TCCL had assumed responsibility by contract for controlling the discharge of sediments and reporting any discharges. However, the Ministry said it received no report from TCCL regarding the discharges that were observed on either dates.

Subsequently, the matter was referred to the Investigations and Enforcement Branch. Following an investigation, the defendant was charged.

Peter’s Drive-In Cleaners Ltd., located in London, Ontario, pleaded guilty in the Ontario Court of Justice on June 7, 2017, to two counts of contravening the Tetrachloroethylene (Use in Dry Cleaning and Reporting Requirements) Regulations made pursuant to the Canadian Environmental Protection Act, 1999. Peter’s Drive-In Cleaners Ltd. was fined $4,000 for each offence.

In addition, an owner of the company pleaded guilty to one count of contravening the regulations, and was was fined $2,000. The $10,000 in fines will be directed to the Environmental Damages Fund.

According to Environment and Climate Change Canada (ECCC), in June 2015, ECCC enforcement officers inspected the facility. The inspection revealed that wastewater containing tetrachloroethylene had not been transported to a waste-management facility and that records had not been maintained. Both acts are in contravention of the Tetrachloroethylene (Use in Dry Cleaning and Reporting Requirements) Regulations.

According to ECCC, tetrachloroethylene, also known as perchloroethylene or PERC, is a chemical used in Canadian dry cleaning. Tetrachloroethylene can enter the environment through the soil, where it can damage plants, and it can find its way into groundwater. It has been listed as a toxic substance under the Canadian Environmental Protection Act since 2000 as it may have an immediate or long-term harmful effect on the environment or constitute a danger in Canada to human life or health.

ES&E Magazine provides vital information for professionals that are engaged in the design, construction and operation of municipal water and wastewater treatment systems, stormwater management, industrial/hazardous waste management and air pollution.